Integers

What is an Integer?

An Integer is a whole number — positive, negative, or zero — with no decimal point. Integers in Frankie have no fixed size limit; they grow as large as needed without overflow.

x = 42
y = -7
z = 0

big = 2 ** 64   # 18446744073709551616 — no overflow
puts big        # 18446744073709551616

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Integer Literals

Write integers directly. Negative integers use a leading minus sign.

count  = 100
offset = -32
zero   = 0
big    = 1000000

Frankie does not currently support underscore separators (1_000_000) or hexadecimal/binary literals. Use plain decimal.

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Arithmetic Operators

Operator	Meaning	Example	Result
+	Addition	10 + 3	13
-	Subtraction	10 - 3	7
*	Multiplication	10 * 3	30
/	Float division	10 / 3	3.333...
//	Integer division	10 // 3	3
%	Modulo (remainder)	10 % 3	1
**	Exponentiation	2 ** 8	256

/ always produces a Float. Use // (Fortran-style) when you want a truncated Integer result.

puts 10 / 3     # 3.3333333333333335  — Float
puts 10 // 3    # 3                   — Integer
puts 10 % 3     # 1                   — remainder
puts 2 ** 10    # 1024

Integer Division and Modulo with Negatives

// truncates toward negative infinity (floor division), consistent with Python:

puts 7 // 2     #  3
puts (-7) // 2  # -4  (floors toward -∞, not toward zero)
puts 7 % 2      #  1
puts (-7) % 2   #  1  (result has the sign of the divisor)

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Compound Assignment

x = 10
x += 3    # x = 13
x -= 2    # x = 11
x *= 4    # x = 44
x //= 5   # x = 8   (integer division assign)
x **= 2   # x = 64
x %= 10   # x = 4
puts x    # 4

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Comparison Operators

Comparisons return a Boolean.

puts 5 > 3     # true
puts 5 < 3     # false
puts 5 >= 5    # true
puts 5 <= 4    # false
puts 5 == 5    # true
puts 5 != 3    # true

Integers and Floats compare naturally:

puts 3 == 3.0    # true
puts 3 < 3.14    # true

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Conversion

# Integer → Float
puts 42.to_f      # 42.0

# Integer → String
puts 42.to_s      # "42"

# Integer → Integer (no-op, but valid in generic code)
puts 42.to_i      # 42

# String → Integer
puts "42".to_i    # 42
puts "-7".to_i    # -7
puts to_int("99") # 99  — standalone function form

# Float → Integer (truncates toward zero)
puts 3.9.to_i     # 3
puts (-3.9).to_i  # -3

Non-numeric strings produce a runtime error — there is no silent fallback to zero:

puts "hello".to_i   # Runtime error

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Math Functions

These standalone functions work on both Integer and Float values:

puts abs(-42)          # 42   — absolute value
puts sqrt(144)         # 12.0 — square root (always returns Float)
puts floor(3.9)        # 3    — round down
puts ceil(3.1)         # 4    — round up
puts round(3.5)        # 4    — round to nearest
puts round(3.14159, 2) # 3.14 — round to n decimal places

puts min(3, 7)         # 3
puts max(3, 7)         # 7
puts clamp(15, 0, 10)  # 10  — clamp between lo and hi
puts clamp(-5, 0, 10)  # 0

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The times Loop

n.times do |i| iterates n times, with i counting from 0 to n-1. This is one of Frankie's most used integer features, borrowed from Ruby.

3.times do |i|
  puts "iteration #{i}"
end
# iteration 0
# iteration 1
# iteration 2

# Without the loop variable
5.times do
  print "* "
end
# * * * * *

The standalone times(n) do |i| form is identical:

times(3) do |i|
  puts i
end

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Sequences

seq(start, stop, step) generates a vector of integers (or floats) from start to stop.

puts seq(1, 5)           # [1, 2, 3, 4, 5]
puts seq(0, 10, 2)       # [0, 2, 4, 6, 8, 10]
puts seq(10, 1, -1)      # [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
puts seq(0, 1, 0.25)     # [0.0, 0.25, 0.5, 0.75, 1.0]

vec(range) builds a vector from a range literal:

puts vec(1..10)     # [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
puts vec(1...10)    # [1, 2, 3, 4, 5, 6, 7, 8, 9]

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Randomness

# Random integer between a and b inclusive
puts rand_int(1, 6)      # dice roll — e.g. 4
puts rand_int(0, 100)    # 0 to 100

# Repeatable with a seed
rand_seed(42)
puts rand_int(1, 100)    # always the same value for seed 42

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Integers in Vectors

Vectors of integers support R-style vectorised arithmetic — operations apply element-wise:

v = [1, 2, 3, 4, 5]

puts v * 2              # [2, 4, 6, 8, 10]
puts v + [10, 10, 10, 10, 10]   # [11, 12, 13, 14, 15]
puts v ** 2             # [1, 4, 9, 16, 25]

# Statistical functions on integer vectors
puts sum(v)             # 15
puts mean(v)            # 3.0
puts min(v)             # 1
puts max(v)             # 5
puts median(v)          # 3
puts stdev(v)           # 1.5811...

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Type Checking

puts is_integer(42)      # true
puts is_integer(3.14)    # false
puts is_integer("42")    # false

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Quick Reference

Category	Operation	Example	Result
Arithmetic	+ - *	10 + 3	13
Float division	/	10 / 3	3.333...
Integer division	//	10 // 3	3
Modulo	%	10 % 3	1
Exponentiation	**	2 ** 8	256
Comparison	== != < > <= >=	5 > 3	true
Compound assign	+= -= *= //= **= %=	x += 1	—
Convert to Float	.to_f	42.to_f	42.0
Convert to String	.to_s	42.to_s	"42"
Absolute value	abs(n)	abs(-7)	7
Square root	sqrt(n)	sqrt(144)	12.0
Rounding	floor ceil round	floor(3.9)	3
Clamp	clamp(n, lo, hi)	clamp(15, 0, 10)	10
Loop n times	n.times do \|i\|	3.times do \|i\|	—
Sequence	seq(start, stop, step)	seq(1, 5)	[1,2,3,4,5]
Random	rand_int(a, b)	rand_int(1, 6)	1–6
Type check	is_integer(x)	is_integer(42)	true